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ID 1:EB072480 Waterford, MI
https://www.netc.com:443/bb/viewtopic.php?f=13&t=336		 Page 2 of 4
Author:  KingCobra [ Fri Aug 23, 2013 10:45 pm ]
Post subject:  Re: Please ignore alerts for station 22 ID 1:EB072480 Waterf
No thank you for answering the questions, it helps so much in helping to understand. Amazing, the window was open! I firmly believe now that your readings were correct.

radiation seems to be heavy in front of a storm even if the storm never reaches you with rain.
Author:  rdesrosi [ Sat Aug 24, 2013 9:10 am ]
Post subject:  Re: Please ignore alerts for station 22 ID 1:EB072480 Waterf
ok test with cover off is complete. There was a noticeable increase at 9am EST as the GM tube was exposed to the sun before I covered it with a black piece of paper. Readings went from a NORM of 24 up to 41 before I covered the tube.

You can see a more dramatic increase again at 9:30am as I took the paper off and replaced the cover. This time spiking up to 82 and triggering a RADCON 3 for my station.

Just after the 9:30 reading was uploaded I replaced the coverer and you can see the reading at 9:40 quickly returned to my stations NORM.

Other than those two spikes no measurable increase in CPM was noticed leading me to draw the conclusion that the readings from my station on Thursday 8/22/13 were caused by exposing the GM tube to direct sunlight for an extended period of time since the event is now repeatable. Since the window faces south you can match up the increase in readings with the sun’s path as it traveled past the open window. Starting at 7am when I put it back up on the open window sill with cover removed through 5pm where the sun has set past the point where it could penetrate the window.

Please feel free to counter my conclusion as I am just a newbe with this station and am still learning the in’s and out’s of radiation monitoring.

So my additional question would be; is that truly a beta reading from Potassium-40 and similar nuclei or just interference with the UV radiation coming from direct sunlight hitting the tube?

And if it is just from UV, why would that cause interference? Does it affect the ionizing properties of the radiation or have an adverse effect on the inert gas in the GM tube (which I assume is Helium but never looked up what is actually in the M4011 tube in my 200)?

Things look a lot "greener" on the map today, not even the other two stations in Michigan are alerting and they always seem to be. So I think I am going to go flying this afternoon after all :)

Sorry for all the additional questions, I am just trying to learn all I can before the fukushima hits the fan…
Author:  KingCobra [ Sat Aug 24, 2013 3:35 pm ]
Post subject:  Re: Please ignore alerts for station 22 ID 1:EB072480 Waterf
Thanks again for the tests and added information.

Although due to your testing results, clearly the sunlight did have an effect on the readings you recorded but I believe some of it too was the storm with beta. Your other questions about why the sunlight causes the change, I am not sure. Those would be good questions to ask on the manufactures GQ's product tech forum. If you ask there or find a previous post with the answer, please post a link to it within this thread for all of us to read too.
Author:  Zehd [ Sun Aug 25, 2013 3:17 pm ]
Post subject:  Re: Please ignore alerts for station 22 ID 1:EB072480 Waterf
I do remember reading somewhere (don't remember where offhand) that the M4011 geiger tubes ARE sensitive to direct sunlight; the site I read that at didn't explain exactly what happens, but I would assume that your surmise of affecting the gas inside the tube is likely. This is probably why other (more expensive) tubes are covered in metal instead of just in a clear glass tube, but as long as the tube is inside the case (so you don't have direct sunlight hitting the tube) it shouldn't matter.

A quick google search did turn up this thread about painting glass geiger tubes.
Author:  KingCobra [ Tue Nov 26, 2013 8:34 pm ]
Post subject:  Re: Please ignore alerts for station 22 ID 1:EB072480 Waterf
As I look through posts in this "NETC Station ID 1: Radiation Monitoring Stations" section of the forum and moving any that do not meet the requirement/rules, I ran across this one and just remembered something I read before...

Some paints have been found to be slightly radioactive.

People might want to think twice before they decide to paint any glass GM geiger counter tubes.
Author:  KingCobra [ Fri Nov 29, 2013 3:59 pm ]
Post subject:  Re: ID 1:EB072480 Waterford, MI
Looking at your current graph, did you recently move your unit from inside to an outside location?
Author:  rdesrosi [ Sun Dec 08, 2013 11:55 am ]
Post subject:  Re: ID 1:EB072480 Waterford, MI
Sorry about the delayed response, been busy working 80+ hours a week launching a new program for my company in addition to trying to get my new house squared aware so I can actually move into it soon.

To answer your question, no I have not done anything to my setup at all. I even made it a point to NOT pack or move anything in the room it sites in to ensure my readings are consistent right up till the time I take it down and move it to the new house, which is 4 houses down.

The only relevant change I made was on 10/22/13 @ 8:09pm EST where I removed the rechargeable 9v battery since that apparently causes issues when fully charges by showing elevated readings.

The only other change, which "should" be totally non-relevant was that my main UPS's batteries failed so I moved the power supply for the Pi and GMC-200 to another UPS with the same run time capacity. Both UPS's are APC's and the backup unit is powering all the same additional equipment that it did when everything was on my primary unit.

That being said since I have not had a chance to look at my sites data for a while, is there an easy way to see historical data for a specific date range? So lets say the week of your last post in this thread?

On a side note, a friend of mine gave me an Asian novelty emergency drink the other day at work. I was about to open it until I noticed on the label that is say made in Japan.. So i pulled out my Atomic Dave Pancake detector and placed it over the bottle and sure enough it was spiking to over 60 CPM where the norm in my office is between 10-20, YIKES! If i get a chance I will make a post dedicated to that.


-Randy
Author:  KingCobra [ Sun Dec 08, 2013 2:15 pm ]
Post subject:  Re: ID 1:EB072480 Waterford, MI
rdesrosi wrote:

On a side note, a friend of mine gave me an Asian novelty emergency drink the other day at work. I was about to open it until I noticed on the label that is say made in Japan.. So i pulled out my Atomic Dave Pancake detector and placed it over the bottle and sure enough it was spiking to over 60 CPM where the norm in my office is between 10-20, YIKES! If i get a chance I will make a post dedicated to that.


Thanks for the updates. When I previous posted, I seen the rise on your graph and just assumed you put it outside. I now see it was simply a rise. Great story about the Japan drink. This is a serious concern that is only going to get worse.
Author:  rdesrosi [ Sun Dec 08, 2013 3:08 pm ]
Post subject:  Re: ID 1:EB072480 Waterford, MI
Yeah scary about that drink from Japan. I left it in a desk in my office so i will bring it home tomorrow and run a few tests with it using my Atomic Dave counter.

Also I found this today, was posted in April 2013 but extremely relevant to this conversation. The girl who gave the drink to me said they are easy to get now is most Asian markets, commented they were coming down in price lately and used to be a little hard to find....

http://www.washingtonsblog.com/2013/04/ ... thing.html
Author:  KingCobra [ Tue Dec 10, 2013 3:06 pm ]
Post subject:  Re: ID 1:EB072480 Waterford, MI
Great link, thank you. 8-)

I shared it in other parts of the forum for others to view.
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